package com.tansun.easycare.core.utils;

import java.io.Serializable;
import java.security.SecureRandom;
import java.util.Random;
import java.util.UUID;

import org.springframework.context.annotation.Lazy;
import org.springframework.stereotype.Service;


@Service
@Lazy(false)
public class IdGen {

	private static SecureRandom random = new SecureRandom();
	
	/**
	 * 封装JDK自带的UUID, 通过Random数字生成, 中间无-分割.
	 */
	public static String uuid() {
		return UUID.randomUUID().toString().replaceAll("-", "");
	}
	
	/**
	 * 使用SecureRandom随机生成Long. 
	 */
	public static long randomLong() {
		return Math.abs(random.nextLong());
	}


	

	public Serializable generateId() {
		return IdGen.uuid();
	}
	
	
	public static String getUuid16()
	{
        int first = new Random().nextInt(8)+1 ;
        int hashCodeV = UUID.randomUUID().toString().hashCode();
        if (hashCodeV < 0) {
            hashCodeV = -hashCodeV;
        }
        return first + String.format("%015d", hashCodeV);
	}
	
	 public static String[] chars = new String[] { "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o",
	            "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z", "0", "1", "2", "3", "4", "5", "6", "7", "8", "9",
	            "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U",
	            "V", "W", "X", "Y", "Z" };
	
	   /**
       * 生成8位UUId
     * 
     * @return
     */
    public static  String generateUuid8() {
        StringBuffer shortBuffer = new StringBuffer();
        String uuid = UUID.randomUUID().toString().replace("-", "");
        for (int i = 0; i < 8; i++) {
            String str = uuid.substring(i * 4, i * 4 + 4);
            int x = Integer.parseInt(str, 16);
            shortBuffer.append(chars[x % 0x3E]);
        }
        return shortBuffer.toString();

    }

	public static void main(String[] args) {
        System.out.println(IdGen.generateUuid8());

	}

}
